PURPOSE: To obtain a magnetic recording medium with superior mechanical strength and electric characteristics by using specified polyurethane resin and cellulose resin as a binder for forming a magnetic layer.
CONSTITUTION: A magnetic recording medium is obtd. by forming a magnetic layer on a substrate such as a polyester film using a binder consisting of polyurethane resin and cellulose resin such as nitrocellulose resin or further contg. an isocyanate compound with low mol. wt. The polyurethane resin cntains ≥15wt% straight chain 4,4'-diphenylmethane diisocyanate as an isocyanate component. The diisocyanate has 2 benzene rings bonded together through a methylene group in the form of a straight chain and isocyanate groups bonded to the p-positions of both the benzene rings.
HIDAKA TOSHIROU
WATAYA SEIJI
MATSUURA TAKESHI